1-Isopropylpiperazine → Hydrochloric Acid

Participants

Reaction Conditions

Reaction Steps

A suspension of 4-(6-chloro-pyridazin-3-yl)-benzonitrile (1 g, 4.64 mmol; prepared as described in U.S. Pat. No. 4,112,095), isopropylpiperazine (0.654 g, 5.1 mmol), DIPEA (1.199 g, 9.27 mmol) and 4-(dimethylamino)pyridine (0.057 g, 0.464 mmol) in DMSO (4 ml) was stirred and heated to 100° C. for 20 h. After cooling to room temperature, the mixture was diluted with dichloromethane (25 ml) and water (35 ml) and stirred for 5 min. The organic phase was separated, washed with water (50 ml) and brine (50 ml), and acidified to pH 2 by addition of 1 N hydrochloric acid. The mixture was extracted with water (30 ml), and the aqueous phase was washed with dichloromethane (10 ml) and concentrated in vacuo to give a solid, which was collected and stripped with ethanol to afford the title compound as a crystalline hydrochloride (1.33 g, 76%).

Provenance & Evidence